Strain and tilt during epitaxial growth of highly ordered In2O3nanorods

Abstract

Precise control over the morphology of one-dimensional (1D) nanostructures is an essential step in the effort to develop nano-devices with exotic properties. Here we demonstrate the formation of highly aligned In₂O₃ nanorod arrays on Y-stabilised ZrO₂(110) grown by oxygen plasma assisted molecular beam epitaxy. The evolution of morphologies, strain and tilt in the In₂O₃ nanorods are studied by atomic force microscopy and high resolution synchrotron-based X-ray diffraction. It is shown that the preferential 1D growth is driven by minimization of the total surface and interface energies. The mismatch of ca. 1.7% between the substrate and the epilayer is accommodated by strain along the [10] direction coupled with tilting of the rods along [001] and [00] directions and contraction in the [110] direction. The present highly ordered In₂O₃ nanorod arrays supported on an insulating substrate are of potential interest for large-scale fabrication of nano-devices.